Enhancing the Reliability of a Contamination Detection Sensors' Network in Water Distribution Systems during a Cyber-Attack

Water distribution systems (WDS) are critical to delivering clean, healthy water at the required quantities and qualities. They are exposed to different kinds of attacks, both physical and cyber, as well as accidental contamination events. In the past years, several events occurred in which contaminants polluted the drinking water. Most of the cases were accidental, but there had also been criminal acts involved. Placing water quality monitoring sensors in designated locations throughout the WDS is considered one of the most effective protection methods for coping with deliberate or occasional water quality contamination intrusions. Sensors, which comprise the water quality monitoring system, communicate over a cyberinfrastructure layer (via radio, cellular, satellite, or wire) and, as such, are exposed to cyber-attacks. Traditionally, sensor placement methodologies included objective functions such as the polluted volume of water consumed or the time for the first detection of possible pollution. However, so far, water quality sensor placement algorithms and tools have not considered cases where the sensor network itself is attacked or malfunctions in a way that part of its components is deactivated. In this study, we propose to develop and demonstrate a methodology for evaluating the impact of a cyber-attack on a sensor network compromising part of its functionality. Our proof-of-concept, using a simple network and straightforward cyber-attack scenario, has revealed potential in analyzing the performance of sensor networks under attack and can provide valuable information for decision-makers in the water utilities and regulators.